[Amended 10-22-2025[
A. 
Site Design Objectives.
(1) 
Design objectives. Proposed developments must be located to preserve and enhance the natural features of the site, including tree canopy, to avoid disturbance of environmentally sensitive areas, to minimize adverse impacts of development on adjoining properties, to minimize the alteration of the natural features of the site and to preserve and enhance scenic points, historic buildings and places and similar community assets which add value and attractiveness to the subdivision and the Town.
(2) 
Residential development. The construction of streets and municipal facilities and of dwellings in a residential development must consider topography, natural features, and drainage and must promote privacy for residents, adequate solar access, tree canopy, planting and other natural elements and consistency with the overall aesthetic appearance of the development.
(3) 
Commercial development. The construction of streets and municipal facilities and of buildings in a commercial development must consider topography, natural features, and drainage and must reduce the impacts of noise, odor, glare and the scale of development on adjoining properties.
(4) 
Unsuitable land. Land that the Board determines to be unsuitable for development due to flooding, improper or adverse drainage, adverse topography, poor soils, bedrock, location of utility easements or other features that the Board determines may be harmful to the safety, health, convenience and general welfare of the present or future inhabitants of the subdivision and or its surrounding area must not be subdivided or developed unless adequate measures are planned by the applicant and approved by the Board to eliminate any short-term or long-term impacts created by development of the unsuitable land.
B. 
Lots; Property Rights.
(1) 
Compliance with Zoning Bylaw. All lots shown on the plan must meet the frontage, area, shape, and access requirements of the Zoning Bylaw. Lots on which a building may be erected shall show the proof circle to confirm lot regulatory, lot area, and lot frontage as required by §§ 135-4.2.2, 135-4.2.3.1, and 135-4.2.4 of the Zoning Bylaw.
(2) 
Relationship of lot to street. Every lot must have adequate access for pedestrians, automobiles, emergency vehicles, such as fire-fighting apparatus and ambulances, and larger vehicles, such as delivery trucks.
(3) 
Lot arrangement. Lots must be arranged so that there will be no foreseeable difficulties in securing building permits to build on all lots due to lack of compliance with the Zoning Bylaw; because of topography, soils, bedrock, improper drainage or other conditions; or in providing practical, workable access to buildings on each lot.
(4) 
Easements.
(a) 
Utility easements, where necessary, must be at least 20 feet wide.
(b) 
When a subdivision is traversed by a watercourse, drainageway, channel or stream, or has a stormwater storage facility, the Board may require an easement of adequate width to conform substantially to the lines of the feature and to offer for the possibility of flooding, protection of banks and adjacent properties, construction or future maintenance and other necessary purposes.
(c) 
Slope easements must be offered where necessary to ensure lateral support and protection of streets and other construction features.
(d) 
No section of a street, pedestrian path, bicycle path, water system, sanitary sewerage system, storm drainage system or another utility system may be approved if it requires a connection to the land of other owners unless appropriate easements are first obtained.
(5) 
Subdivision straddling municipal boundaries. Whenever access to the subdivision or any lot in it is required to cross land in another town or city, the Board may require documentation that access for the intended use has been legally established in that town or city as a public street or as part of an approved subdivision in accordance with local zoning. In general, lot lines should be laid out so as not to cross municipal boundaries.
(6) 
Self-imposed restrictions. If, as part of a subdivision application, the applicant or owner places voluntary restrictions on any of the land contained in the subdivision that is greater than the requirements of these Regulations or Zoning Bylaw, such restrictions or references to them must be shown on the definitive plan and recorded in the Registry of Deeds.
(7) 
Bounds.
(a) 
Permanent reference bounds for surveying must be set:
[1] 
Along each right-of-way line at all intersections, angle points, points of change in direction or curvature of streets, and at the two corners of each lot that abuts the right-of-way; and
[2] 
Along each line of any easement at angle points, points of change in direction or curvature.
(b) 
If a permanent bound is set on a long straight line, bounds must be set so that each is visible, or not more than 500 feet, from the next bound in each direction.
(c) 
Permanent bounds must be of granite or reinforced concrete six inches square and three feet long with a one-inch deep one-half-inch diameter drill hole in the top. Permanent bounds must be set in bank run gravel and must be set flush with the surface of the ground per the Standard Specifications. Where the soil makes the setting of permanent bounds impractical, alternate types of permanent monumentation may be used with the prior approval of the Town Engineer.
(8) 
Markers. In addition to locations where permanent bounds are required, a permanent reference marker for surveying must be set along each lot line at angle points, points of change in direction or curvature. Permanent markers must be metal pipes or pins at least 24 inches in length and must be embedded in the ground so that they are not easily removed or shifted from the point they mark.
C. 
General Construction Requirements.
(1) 
Construction specifications. If the subdivision plan proposes construction for which standards or specifications are not given by these Regulations, the Board's Development Regulations, or the Town's Standard Specifications, the Massachusetts Highway Department Standard Specification for Highways and Bridges, latest edition, will apply. If there is a difference between the Town's Standard Specifications and the Massachusetts Highway Department Standard Specification for Highways and Bridges, the Town Engineer must determine which standard or specification will apply.
(2) 
Reimbursement for extra construction. The Board may require an applicant to install municipal services and construct ways of greater width or size than the requirements for the subdivision alone with the added cost to be reimbursed by the Town. Under no circumstances will a developer be reimbursed for the construction of a street with a pavement less than 33 feet wide, nor will a reimbursement be made for extending streets and utilities to the subdivision's boundaries.
(3) 
Improvements across entire frontage. The improvements required by these Regulations must be constructed across the entire frontage of any lot the subdivision of which is approved by the Board.
(4) 
Accessibility. All proposed improvements must comply with MGL c. 22, § 13A and all regulations adopted under it.
[Amended 10-22-2025]
A. 
Complete Streets Design Objectives. All subdivision street plans and designs must provide appropriate accommodations for all transportation system users, including pedestrians, cyclists, transit users, and motorists. Complete streets are designed and operated to enable safe access for users of all ages and abilities. Street designs should be developed in a context-sensitive manner in which consideration is given to the surrounding physical environment, land uses, as well as the location of existing and other planned infrastructure to support a multi-mode transportation network.
(1) 
General objectives. The subdivision street system must be designed to:
(a) 
Permit the safe, efficient and orderly movement of motor vehicles, pedestrians, and bicycles.
(b) 
Meet, but not exceed, the needs of the present and projected future population to be served.
(c) 
Offer easy and prompt access by emergency vehicles, such as fire, police and ambulance vehicles, and to permit effective delivery of Town services, such as snow removal, school bus, and refuse removal services.
(d) 
Contribute to a safe and efficient Town-wide system of movement of motor vehicles, pedestrians, and bicycles.
(e) 
Promote connections for pedestrians, bicycles, and motor vehicles between adjacent neighborhoods and more direct access to public facilities, such as schools, recreation areas, and open space.
(f) 
Provide alternatives to the Town's few arterial streets to connect adjacent neighborhoods.
(g) 
Promote public transportation and increased pedestrian and bicycle accommodations in order to reduce vehicular congestion and environmental pollution.
(h) 
Minimize the long-term costs for maintenance and repair of streets.
(i) 
Enhance the appearance of the subdivision and the Town by achieving a visually attractive streetscape.
(2) 
Residential subdivisions. In addition, the street system in a residential subdivision must be designed to:
(a) 
Discourage use of streets in residential neighborhoods by through traffic that originates or has a destination:
[1] 
Outside of the Town.
[2] 
In a commercial area.
[3] 
In residential neighborhoods in the Town that are a mile or more away.
(b) 
Protect the residential character of the development by encouraging safe-speed travel within the subdivision and reducing noise and fumes.
(c) 
Promote safe travel by bicycles and pedestrians and, where possible, offer facilities for them separated from automobiles.
(3) 
Commercial subdivisions. In addition, the street system in a commercial subdivision must be designed to:
(a) 
Encourage carpooling, van services, cycling, and public transportation and a reduction in single-occupant automobiles.
(b) 
Reduce congestion on nearby streets and preserve adequate transportation capacity and user safety at affected intersections and street segments.
B. 
Layout and Alignment of the Street System.
(1) 
Must connect to a public street.
(a) 
Each street within a subdivision must connect to and be accessible from the public street system, either directly or via some combination of:
[1] 
Streets approved as part of another definitive subdivision plan which have either been constructed in accordance with that plan or for which adequate surety exists to guarantee satisfactory completion of the street;
[2] 
Streets other than those above which are built to the same design standards as new subdivision streets constructed in compliance with these Regulations; or
[3] 
One or more other streets in the subdivision.
(b) 
In order to meet these requirements, the applicant may improve existing streets at its own expense. The Board may not approve a subdivision plan that requires improvement of a street if a competent legal opinion is presented that the applicant does not have the necessary rights to make such improvements unless the Town Counsel provides an opinion that any potential legal impediments to such construction have been removed.
(2) 
Streets continuous. Where there is more than one street within a subdivision, streets must be connected into one continuous system.
(3) 
Intersections.
(a) 
Streets must be laid out to intersect as nearly as possible at right angles, and in no case at less than a seventy-five-degree or more than a one-hundred-five-degree angle.
(b) 
New subdivision streets may be constructed at an intersection of two existing streets if the proposed subdivision street is aligned opposite one of the existing streets.
(c) 
An intersection of two streets may not be within 125 feet of any other existing or proposed intersection, unless aligned directly across the street, as measured between the points of intersection of the center lines of the intersecting streets.
(4) 
Location. New rights-of-way shall be located at least 10 feet from any lot outside the subdivision except as provided below.
(a) 
This subsection shall not apply to easements reserved under § 175-7.2C but not constructed.
(b) 
This subsection shall not apply to the portions of rights-of-way providing adequate sight distance at intersections required by § 175-7.2E(12).
(c) 
Where an existing right-of-way is extended, this subsection shall not apply to lots fronting on the existing right-of-way.
(d) 
This subsection shall not apply to proof plans not approved for construction.
C. 
Extension to Adjoining Land.
(1) 
Easement reserved for an extension to adjoining land. When land adjoining the subdivision can be developed, the subdivision plan must allow for the future extension of streets and other public facilities to the adjoining land. The subdivision plan must reserve an easement to the adjoining land for the future extension of the street and other public facilities.
(2) 
Reserve strips prohibited. Where a way within the subdivision passes within 25 feet of an adjacent property, the subdivision plan must reserve an easement providing access from the way to the adjacent property.
(3) 
Reconstruction of street if development of adjoining land occurs later. If the adjoining land is later developed, the developer of that land may extend the street and utilities to the adjoining land. Such construction must include the removal of any turnaround. Any land within the right-of-way that was part of the turnaround and is no longer needed for an extended right-of-way must be landscaped and deeded to the abutters.
(4) 
Utility stubs extended.
(a) 
The Board may require the developer to construct stubs of utility lines and other underground services and facilities to the edge of the right-of-way so that future extension of the street and utilities can be made without digging trenches in the street.
(b) 
The Board may require the developer to construct a wye stub of newly constructed utility lines to the edge of the right-of-way of a street to serve lots that abut the street but are not in the subdivision so that those lots may connect to the Town system later without digging trenches in the street.
D. 
Street Classification.
(1) 
Compliance with the Classification System.
(a) 
The street type is defined by assessing the street's proposed role in the Town's (and regional) transportation system, together with its surrounding built and natural environment. Lexington is generally suburban in character, with some parts appearing rural and some quite urban, which makes identifying the unique or project-specific contextual elements crucial to determining the appropriate design.
(b) 
For the purposes of an application, the Board will determine the classification of each proposed street.
(2) 
Classes. The street type reflects its degree of local access and regional connectivity as described below:
(a) 
Arterials. Arterials have a high to moderate degree of regional connectivity at a wide range of speeds with a low to high level of local access. Examples include Waltham Street and Massachusetts Avenue.
(b) 
Collectors. Collectors have a low to moderate degree of regional connectivity, at a wide range of speeds, with a higher degree of local access than arterials. Grant Street, Hill Street, and Lincoln Street are examples of collectors.
(c) 
Local streets. Local streets have a low to no degree of regional connectivity, low speeds, and a high degree of local access.
(d) 
Minor streets. Minor streets are a subset of local streets that serve, directly or indirectly, fewer than 10 existing, proposed, or potential dwelling units. Minor streets are typically, but not always, dead-end streets.
(3) 
Street Names. Street names must be different enough in sound and in spelling from other street names in Lexington so as not to cause confusion. A street that is planned as a continuation of an existing street must have the same name. The extension of a street to connect to another street with a different name must have the name of the longer street. The Board, after consultation with the Town's public safety officials, determines the name of the street.
(4) 
Street name signs. Street signs must be erected on two-inch inside diameter posts at all street intersections per the Standard Specifications. A temporary street name sign with black letters four inches long on light background must be erected at the time work is started in that part of a subdivision at all points where permanent signs will be required. The developer must keep complete visibility of street name signs until they are replaced by permanent signs that follow the Town's specifications, at the developer's expense.
E. 
Design Standards for Streets and Rights-of-Way.
(1) 
Design standards for streets and rights-of-way.
(a) 
These standards draw from and rest upon several important street design resources. These standards are consistent with, and in the case of silence or conflict should be referred to those described in:
[1] 
The 2011 edition of "A Policy on Geometric Design of Highways and Streets," by The American Association of State Highway and Transportation Officials (AASHTO);
[2] 
The Massachusetts Department of Transportation's specific guidance on complete streets design standards found in the following publications:
[a] 
Project Development and Design Guide (2006);
[b] 
Healthy Transportation Policy Directive (P-13-0001, 2013);
[c] 
Engineering Directive E-14-006 (2014); and
[d] 
Separated Bike Lane Planning and Design Guide (2015).
[3] 
The many related resources referenced in the above, especially those aimed at achieving flexibility around pedestrian and bicycle facilities,
(b) 
The standards below are not an attempt to provide every detail needed to design a right-of-way, but highlight key elements where the Town wishes to provide specific guidance to create context-sensitive rights-of-way.
Standard
Minor
Local
Design speed (miles per hour)
25
25
Right-of-way cross-section elements
Sidewalks
Number
1
1
Width (feet)
5
5
Planting strip
Minimum width (feet)
4
5
Shoulders
Width (feet)
1
2
Travel lanes
Number
2
2
Width (feet)
9
10
Minimum grade
1%
1%
Maximum grade
8%
8%
Maximum grade within 75 feet of intersection
2%
2%
Other Design Elements/Criteria
Minimum overall rights-of-way width (feet)
40
50
Minimum intersection rounding radius (feet)
25
25
Minimum distance between the new ROW to any lot line of any lot situated outside of the subdivision, except as in § 175-7.2B(4)
10
10
(2) 
Collector and arterial design. Proposed subdivisions that require collector- or arterial-scale rights-of-way should refer to the design resources listed in Subsection E(1) above.
(3) 
Cross slopes. The cross slopes of the travel lanes are 3/8 of an inch per foot. The maximum cross slope of the planting strips is 3:1. The maximum cross slope for sidewalks is 1.5%.
(4) 
Bicycle accommodations. All proposed streets must make adequate provisions for cyclists. For minor and local streets, these accommodations are likely to be met by sharing the travel lane, without the need for formal markings or signage. On collectors and arterials, however, depending on the context, adjustments to travel lane widths, shoulder widths, pavement markings, dedicated bicycle lanes, or separated lanes may be required.
(5) 
On-street parking. Due to their width, on-street parking is prohibited on minor streets. Local streets, by contrast, can informally accommodate parking on one side of the street. On-street parking on collectors and arterials should be designed carefully in consideration of other travel lane users, such as cyclists.
(6) 
Changes in direction. Any change in direction of right-of-way tangents must be connected by either a horizontal curve or an intersection.
(7) 
Dead-end streets.
(a) 
A dead-end street may not be longer than 650 feet from the point of beginning following the center line to the furthest point on the right-of-way line. The point of beginning of a dead-end street or way or of a system of dead-end streets or ways is the point of intersection of street center lines with a street of which there are two or more distinct vehicular access routes to the general street network of the Town.
(b) 
A dead-end street shall be a minimum of 150 feet from the point of the beginning following the center line to the furthest point on the right-of-way line on the turnaround.
(c) 
A street sign stating "Dead End" or "Not a Through Way," satisfactory to the Town Engineer, must be installed.
(d) 
Dead-end street turnaround design standards.
[1] 
Every dead-end street must Terminate with a sixty-foot radius right-of-way line with a landscaped center island.
[2] 
The pavement must have an outside turning radius of at least 50 feet.
[3] 
The pavement must have an inside turning radius of at least 25 feet.
[4] 
Alternative plans must include an analysis and evaluation of fire apparatus maneuvers throughout the turnaround created by swept path analysis and turn simulation software.
(8) 
Center line of street. The center line of the paved section of the street must follow the center line of the right-of-way.
(9) 
Driveway aprons. Driveway aprons must be constructed to serve each lot, graded to offer unimpeded drainage in the gutter, and constructed to the same standards as the street to the actual driveway width but in no case less than eight feet nor greater than 20 feet wide for the entire distance between the exterior right-of-way line and the paved section of the street.
(10) 
Curbs and gutters.
(a) 
Curbing is required to offer for safety, stormwater management, and delineation and protection of the pavement edge and to prevent erosion. Except where specified below, a continuous, low profile, Cape Cod style berm of bituminous concrete must be provided as an integral part of each new street.
(b) 
Vertical granite curbing must be installed:
[1] 
At the back of catch basins that are at low points;
[2] 
On all sections of a street with a grade greater than 5%;
[3] 
At all corner roundings; and
[4] 
On all collector and arterial streets.
(c) 
The design, dimensions, and installation of all granite or bituminous curbing must follow the Town's Standard Specifications.
(11) 
Slopes and walls.
(a) 
Wherever the grade of the approved street differs from the grade of the adjacent land or where otherwise necessary for public safety, in the area beyond the sidewalk or landscaped planting strip, the developer must erect retaining walls and guardrail fences or offer slopes no steeper than one foot vertical to three feet horizontal in fill and one foot vertical to two feet horizontal in cut to ensure proper protection and lateral support.
(b) 
No retaining wall may have a height above finished grade greater than five feet. Where necessary, a series of retaining walls may be constructed in a terraced effect, provided the horizontal distance between the outside face of one wall is at least four feet from that of the next wall.
(c) 
Landscaping must be provided on slopes and on the terraces between retaining walls to reduce the visual impact of the construction. Such walls, fences, slopes, and planting are subject to the Board's approval as to location, design, and dimensions and must be constructed in a manner satisfactory to the Town Engineer.
(12) 
Sight distance, alignment, and profile. To ensure proper sight distances, alignment and profile of proposed streets designers must use the methodology laid out in AASHTO's "A Policy on Geometric Design of Highways and Streets," referenced above. The Policy describes in detail how to calculate stopping sight distances, decision sight distances, passing sight distances, and horizontal and vertical profile.
(13) 
A development should consider future sidewalks or other complete streets improvements within the development and where the new subdivision road connects to the existing road. New roads should connect the sidewalk to an existing sidewalk system. An applicant should consider locations of hardscaping, landscaping, utility poles, fire hydrants, and other site appurtenances that could create new hazards in close proximity to the right-of-way.
F. 
Street Construction.
(1) 
Construction standards and procedures. The following construction and installation standards apply:
(a) 
The area between the right-of-way lines must be cleared and grubbed except for those trees intended to be preserved as street trees.
(b) 
All excavation must conform to the lines and grades shown on the approved definitive subdivision plan. Where mucky soil, ledge or clay is encountered within the right-of-way, it must be removed entirely and, where necessary, replaced with ordinary borrow or other materials specified in Massachusetts Highway Department Standard Specifications for Highways and Bridges, latest edition. Where water is encountered or is expected to be encountered within four feet of the finished grade of the street, subsurface drainage, of a design acceptable to the Town Engineer, must be constructed.
(c) 
Boulders or ledge must be removed to a depth of at least 24 inches below final grade when within the area to be paved. Extensive ledge areas may require the installation of interceptor sub drains or perforated pipe. Where street and shoulder grades require more than two feet of cut or fill, retaining walls may be required along abutting property lines unless a suitable alternative is shown, such as an earth slope one foot vertical to two feet horizontal. In such cases, a slope easement of adequate width must be obtained.
(d) 
The paved section of a street must conform to the current version of the Town of Lexington's Standard Street Construction Details. All materials used in the construction of streets must conform to the Town's Standard Specifications or, when not covered by the Standard Specifications, to the Massachusetts Highway Department Standard Specifications for Highways and Bridges, latest edition.
(2) 
Restoration of existing streets. Whenever the construction of utilities, connection to existing services, or facilities requires opening a street, the developer must reconstruct the existing pavement, as follows:
(a) 
By cold-planing the entire width of the street to a depth of 1.5 inches, from the point of curvature of the curb rounding across the proposed subdivision street to the point of tangency of the opposite curb rounding; and
(b) 
Overlaying the cold-planed area with a one-and-one-half-inch finish course of bituminous concrete.
[Amended 10-22-2025]
A. 
Sidewalks.
(1) 
Location. Sidewalks must be located within, and next to, the exterior line of the right-of-way. Sidewalks must be a uniform distance parallel to the paved section of the street and separated from it by a landscaped strip. However, in order to avoid mature trees in the proposed right-of-way that is to be preserved, applicants may deviate from this standard without the need for a waiver, provided they remain within the right-of-way.
(2) 
Alternative locations. The applicant may propose, or the Board may require, that all or some of the walks be located within easements rather than within the right-of-way of the street. The width and construction of walks in easements must be the same as if within a street right-of-way.
(3) 
Construction. Sidewalks construction must conform to the Town's Standard Specifications.
B. 
Footpaths and Trails.
(1) 
Where required. The Board may require the construction of a footpath or trail to offer access to open space, recreational areas, streets, footpaths, trails, bicycle paths, or recreational paths located either within the subdivision or on adjoining land.
(2) 
Objectives for footpaths and trails. Footpaths and trails should be individually tailored, in width and material, to take full advantage of the area's unique natural surroundings with attention to the following objectives and standards:
(a) 
Build for durability by:
[1] 
Finding the most stable, well-drained soils that can bear the weight of pedestrian traffic;
[2] 
Building boardwalks where the soil is wet or unstable; and
[3] 
Using a switchback plan on slopes to inhibit erosion.
(b) 
Minimize environmental impact by:
[1] 
Disturbing the environment surrounding the trail as little as possible;
[2] 
Leaving trees that will offer a natural check on the amount of undergrowth that will require maintenance;
[3] 
Designing for proper drainage;
[4] 
Harmonizing the trail with its environment; and
[5] 
Using natural construction materials, such as dirt, cobblestones, or wood, where appropriate.
(c) 
Offer privacy for adjacent landowners by one or more of the following:
[1] 
Constructing a berm, fence, or combination of both;
[2] 
Planting trees and shrubs; and
[3] 
Allowing the natural vegetation to reclaim the area if it will offer adequate protection.
(3) 
Path easements. Easements for footpaths or trails must be at least 10 feet wide. Easements providing public access over these paths and trails are required.
(4) 
Identification. A sign or identification for a footpath or trail must:
(a) 
Be placed at the entrance and junctions of trails; and
(b) 
Be coordinated with the color of the existing signage used in the conservation areas in Lexington;
C. 
Bicycle Path or Recreational Path.
(1) 
The Board may require the construction of a bicycle path or recreational path:
(a) 
To offer a connection to a Town bicycle path or recreational path located on adjoining land or streets; or
(b) 
Where the path would be part of an existing or proposed Town bicycle path or recreational path system or of bicycle path or recreational path leading to a public school.
(2) 
Path easements. Easements for bicycle paths or recreational paths must be at least 10 feet wide. Easements providing public access over these paths and trails are required.
(3) 
Construction. A bicycle path or recreational path must be at least 10 feet wide and constructed in accordance with the Town's Standard Specifications.
A. 
Standards for Water and Sewer Service.
(1) 
Construction requirements. All elements of the water and sanitary sewer service must be designed to comply with the Town's Water, Sewer and Drain Regulations and the Standard Specifications.
(2) 
Connection to Town system. Water and sanitary sewer mains must connect to the municipal water supply and sanitary sewer systems, respectively.
B. 
Water Mains.
(1) 
Objectives. Water mains, laterals, and appurtenances must be designed to offer adequate water service for the needs of residents and for fire suppression.
(2) 
Looped water system. The water system must be designed to form a continuous loop with existing or proposed water mains.
(3) 
Fire hydrants. Fire hydrants must be spaced not more than 500 feet apart. A copy of the plan showing fire hydrant locations must be submitted by the Board to the Fire Chief for his or her comments and recommendations.
C. 
Sanitary Sewers.
(1) 
Objectives. Sanitary sewers, including all appurtenances, must be designed to connect all lots in a subdivision to the municipal sewer system for treatment and disposal of sewage.
D. 
Electric Power and Communication Lines.
(1) 
Installation. All electric power lines and communication lines must be installed in underground conduits. Communication lines must include, but not be limited to, telephone, security alarm, and cable television. To ensure that future providers have access to the development, additional conduits must be provided.
(2) 
Streetlighting. The developer must show provisions for streetlighting on a plan subject to the approval of the Town Engineer. The developer must install the conduit underground and construct the bases. Poles and streetlights may not be installed without the prior written approval of the Town Engineer.
A. 
Objectives. Projects must be developed to maximize stormwater recharge within the site, minimize direct overland runoff onto adjoining lots, streets, and watercourses, and ensure that the Town can meet the requirements of its National Pollutant Discharge Elimination System (NPDES) general permit.
B. 
Drainage Easements.
(1) 
Where it is necessary to carry drainage across lots within the project, drainage easements must be provided of such width and construction as will be adequate to accommodate the volume and velocity of the runoff. However, in no case may the easements be less than 20 feet wide.
(2) 
When a proposed drainage system will carry water across land outside the project boundaries, appropriate drainage rights must be secured by the applicant and referenced on the definitive plan.
C. 
Standards for Stormwater Management.
(1) 
Construction requirements. All projects subject to this section must be designed to comply with the requirements for above-threshold projects detailed in Article VI, Stormwater Management Regulations, of Chapter 181 of the Code of Lexington.
[Amended 10-22-2025]
A. 
Objectives and Applicability.
(1) 
Objectives. The Board determines that:
(a) 
Trees and other plant materials planted within or along the right-of-way as part of a coordinated landscape plan improve the appearance and economic value of a subdivision;
(b) 
A landscaped island in the center of a turnaround is better than a paved surface covering the entire island;
(c) 
The owners of the lots that have frontage on the turnaround, individually and collectively, should support the landscaping in such islands, and the owners of other lots that have frontage on sections of the right-of-way within which landscaping is planted should support that landscaping;
(d) 
Every effort must be made to preserve existing trees within the proposed right-of-way as well as within individual lots shown on the subdivision.
B. 
Street Trees.
(1) 
Location. Street trees must be planted, at the developer's expense, on each street within the tract being subdivided. Trees should be planted within the right-of-way's planting strip(s) and spaced between 27 feet and 35 feet apart on center.
(2) 
Characteristics. Proposed street trees must meet the following standards:
(a) 
Proposed street trees must be of the applicable USDA Zone hardiness, licensed nursery stock with good root development and branching characteristics with a one-year warranty.
(b) 
No more than 50% of any one genus may be proposed.
(c) 
Proposed street tree species must be native indigenous to the region. A list of recommended tree species can be found in the Massachusetts Division of Fisheries and Wildlife's publication "The Vascular Plants of Massachusetts: A County Checklist," the Board's preferred planting list.
(d) 
Be a minimum size of three inches in caliper, measured four feet from the ground level, and eight to 10 feet of height in place.
(e) 
Be planted in holes of a depth and width of two times the diameter of the root ball. Trees must be planted at their proper depth, in good quality topsoil, and securely staked.
C. 
Cul-De-Sac Plantings. The center island of a cul-de-sac must be landscaped.
D. 
Restoration of Slopes. All cut and fill slopes subject to erosion and adjoining the right-of-way must be planted with suitable well-rooted, low-growing plant materials as shown on the landscape plan. Plants or perennial grass must be suited to the adjoining landscape and located to offer adequate cover. The Board may require the planting of sod and other erosion control measures where called for.
E. 
Soils. Where soils have been compacted and where existing trees will not be adversely affected by the process, soil profile rebuilding methods shall be employed before landscaping begins.
A. 
Designation for Reservation. The Board may require the designation of one or more parts of the subdivision tract for reservation for three years for park, playground, open space or other municipal purposes. The reservation of land may not be unreasonable in relation to the size of the tract being subdivided and to the prospective uses of the reserved land.
B. 
Plan Notation. If the Board designates land for reservation for municipal purposes, a notation must be made on the definitive subdivision plan concerning the area being reserved and the requirement that no street, utilities, building, or other improvements within the boundaries of the land being reserved may be made for three years from the date of endorsement of the plan without the Board's prior written approval.
C. 
Action by Town Within Three Years. During the three-year reservation period, the Town may choose to buy any or all of the reserved land and must justly compensate the owner for the land acquired. If the Town does not choose to buy the land within the three-year reservation period, the developer may go ahead with improvements per the approved subdivision plan.